Sofa



FIG. 1 is a perspective view of a sofa showing my new design from the front, right end and top;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof; and,

FIG. 4 is a right end elevational view thereof, the left end being a mirror image thereof.

The bottom is plain. 

The ornamental design for a sofa, as shown and described. 